The Hispanic Community Health Study / Study of Latinos (HCHS/SOL) is a multi-center epidemiologic study in Hispanic/Latino populations to determine the role of acculturation in the prevalence and development of disease, and to identify risk factors playing a protective or harmful role in Hispanics/Latinos. The study is sponsored by the National Heart, Lung, and Blood Institute (NHLBI) and six other institutes, centers, and offices of the National Institutes of Health (NIH). Study goals include studying the prevalence and development of disease in Hispanics/Latinos, the role of acculturation, and to identify risk factors that play protective or harmful roles in Hispanics/Latinos. The target population of 16,000 persons of Hispanic/Latino origin, specifically Cuban, Puerto Rican, Mexican, and Central/South American, to be recruited through four Field Centers affiliated with San Diego State University, Northwestern University in Chicago, Albert Einstein College of Medicine in the Bronx area of New York, and the University of Miami. Seven additional academic centers serve as scientific and logistical support centers. Study participants aged 18-74 years will undergo an extensive clinic exam and assessments to determine baseline risk factors. Annual follow-up interviews will be conducted for 2-4 years to determine health outcomes of interest. Study results will be disseminated through scientific journals and also conveyed to the communities involved in the study in order to improve public health at the local level.